Electrical measuring instruments



D. F. ROERTY ELECTRICAL MEASURING INSTRUMENTS Original Filed Aug. 13, 1958 April '7, 1964 3 Sheets-Sheet 1 April 7, 1964 D. F. ROERTY ELECTRICAL MEASURING INSTRUMENTS original Filed Aug. 13, 1958 3 SheehS-Sheet 2 Fig.2

April 7, 1964 D. F. ROERTY K 3,128,144

ELECTRICAL MEASURING INSTRUMENTS Original Filed Aug. 13. 1958 3 Sheets-Sheet 3 United States Patent i 7 Claims. (Cl. 346--1.40)

This invention relates to electrical measuring instruments and has particular relation to instruments of the recording type.

Recording instruments have previously been constructed to record variable electrical quantities such as voltage and current. ln ysuch instruments, a measuring device including a movable part is ordinarily provided for actuating a suitable indicator, such as a pen, which imposes markings upon a suitable chart for rindicating the measured quantity.

When a pen is utilized, it is necessary to provide means for supplying ink to thet pen. This has been accomplished in the past by providing an ink container with flexible tubing leading from the container to the pen with the tubing connected between the pen and ink container for movement with the pen.

With such arrangement, a number of problems arise. For example, the problem arises as to the elfect upon movement ofthe pen imposed by unpredictable movements of the liexible tubing. This problem is particularly troublesome in instruments employing a pen which is irectly connected to the movable part of the measuring device. Such instruments may be referred to as direct acting instruments. In such direct acting instruments relatively low values of torque are applied to the pen as compared to the torque applied in instruments of the indirect acting type ywherein torque amplifying devices, such as linkages, are interposed between the pen and the movable part.

When such liexible tubing is utilized in instruments of the direct acting type, it has been noted that the tubing applies torque to the pen which constitutes an appreciable percentage of the total torque applied to the pen. It has been further observed that the torque applied by the tubing to the pen for a given energization of the measuring device may varyr considerably due to inconsistent and non-repetitions movements of the tubing resulting from twisting and bending of the tubing in response to repeated movements of the pen. It has been further noted that such torque variations not only result in undesirable movements of the pen relative to its associated chart but also adversely affect the calibration of the instrument.

In addition, it has been observed that plastic tubings employed in recording applications possess certain inherent yundesirable characteristics which adversely affect the operation of recording instruments. For example, such plastic tubing exhibits permeability to gases which may result in failure of the inking system due to the formation of air bubbles in `the tubing. Further, plastic tubing is observed to exhibit a so-called memory eliect whereby in yrecorder applications the recorder indication varies as a function of time.

According to the present invention, a recording instrument is provided including improved means for supplying ink to a pen assembly from an ink container. In the present' invention, a recordingy instrument is provided with ilexible metallic tubing supplying ink from an ink container with the tubing arranged so as to be movable with the pen along a predetermined'and repetitions course to substantially eliminate undesirable effects of movements of thetubing upon movements of the pen.

3,128,144 Patented Apr. 7, 1964.

Akprevious construction has also employed a sealed inking system which includes a compressible sealed plastic saclr as an ink container. When this construction is utilized, the iiow of ink may be initiated by compressing the sack to force ink from the sacl-f` through the tubing into the pen. Heretotore, considerable di'lculty has been experienced in initiating the ink ilow due to numerous and curnbersome operations involved in .manipulating portions of the recorder mechanism to expose the sack and in handling the sack to eiect compression thereof.

In the present invention, a recording instrument isy provided including an inlring system having a compressible ink sack with improved means for compressing the sack to initiate ink flow without disturbing the instrument mechanism and without yhandling of the sack. Such means preferably includes a manually actuable plunger which is actuable by an operation performed at the front of the instrument.

When an inking system as described is utilized, the further problem arises as to the manner of mounting the ink sack to prevent accidental displacement thereof. For example, considerable diiiiculty has previously been encountered in mounting the sack in its operative position to yprevent displacement of the sack therefrom during shipment of the instrument. v

According to the invention improved means are provided to securely mount the compressible sack in an operative position against accidental displacement. Such means mayinclude a resilient part which is normally biased against a portion of the sack to mount the sack and which is readily dellectable from its sack-mounting position to a position permitting rapid removal of they sack from its mounted position. Preferably, the sack compressing means and the sack-mounting means include common parts.

In a preferred embodiment of the invention, a direct acting recording instrument is provided including a measuring device having a part rotatable about an axis in re- A pen assembly i sponse to energization of the device. is directly connected to they moving part for rotation therewith about the axis of the moving part. The tubing is formed of a metallic material and includes a portion intermediate its ends which is curved about the axis of the movable part.

According to the present invention, the tubing is in the form of a spring preferably of helical configuration having ends connected respectively to a stationary support and to the movable assembly. This arrangement results in consistent and repetitious movements of the tubing along a predetermined course in response to repeated movements of the pen. by the tubing is, therefore, substantially constant for a given energization of the measuring device and may be substantially compensated in the calibration of the instrument.

The peny assembly is further mounted for pivotal movement about `an axis which is transverse to the axis of the rota-table part. The invention provides further that the tubing is connected to the pen along a line which is common to the axis of pivotal movement of the pen.

The sack compressing and mounting means preferably includes a pair of resilient members each mounted for deection towards and away from the other; These members include portions which yare normally biased towards each other to pinch an ink-free portion of the sack for retaining the sack against accidental displacement.

In order to compress the sack to initiate ink ilow, one of themembers is deflected against the ink-iilled portion of the sack to simultaneously move the associated pinching portion away from its pinching position and to force inlt from the `sack through the sack neck into the tub- The torque applied to the penr r3 ing. The sack may be freed from its captive position by deflecting the other member to move its pinching portion away from its pinching position.

lt is, therefore, an object of the invention to provide a recording instrument `including a measuring device for actuating a recording pen with improved means for supplying ink to the pen from an ink container.

It is another object of the invention to provide a recording instrument including a measuring device for actuating a recording pen with flexible metallic tubing supplying ink from an ink container to the pen with the tubing mounted and arranged such that movements of the tubing in response -to repeated movements of the pen are consistent and repetitious.

It is still another object of the invention to provide a direct acting recording instrument including a measuring device having a movable part directly connected to a recording pen with flexible helical metallic .tubing supplying ink to the pen from an ink container such that the torque applied to the pen by the tubing is substantially constant for a given energization of the measuring device.

It is a further object of the invention to provide a recording instrument including a measuring device for actuating a recording pen with tubing supplying ink from a compressible sealed ink container to the pen with improved means `for compressing the container Ito initiate the liow of ink from the container through the tubing to the pen.

It is a still further object of the invention to provide a recording instrument including a measuring device for actuating a pen with flexible tubing connected between the pen and a compressible sealed ink container with improved means for mounting the container against accidental displacement.

Other objects of the invention will become apparent from the following description taken in conjunction with the accompanying drawings, in which:

FIGURE 1 is a view in yfront elevation of a measuring instrument with parts removed and with parts. broken away embodying the teachings of the present invention;

FIG. 2 is a view in side elevation of the instrument of FIG. 1 with parts broken away, with parts removed and with parts shown in section;

FIG. 3 is a view in side elevation of a portion of the instrument of FIG. 2;

FIG. 4 is a view similar to FIG. 3 illustrating the portion of FIG. 3 in a different condition; and

FIG. 5 is a view in rear elevation of the portion shown in FIG. 3.

Referring now to the drawings, there is illustrated a recording instrument for recording a variable electrical quantity such as voltage or current. The instrument is represented generally by the numeral 1l and includes a casing 3 Within which operating parts of the instrument are contained as best shown in FIG. 2. The casing 3 includes a front cover section 5 which is removably associa-ted with a rear supporting section 7. The front section 5 includes a transparent window 9 through which parts of the instrument supported by a plate 1t) within the section 7 may be observed.

The instrument includes a measuring device 11 which may be of any suitable construction. In the embodiment illustrated, the device 11 includes a magnetic structure 13 preferably `formed of a plurality of magnetic laminations 15, each having the configuration illustrated in FIG. 1. The laminations 15 may be constructed of any suitable magnetic material, such as silicon steel, and are fastened together in any suitable manner as by bolts y16. The structure 13 includes a rim portion 17 having an inner periphery from which extend a pair of spaced opposed poles 19 and 21. A pair of windings 23 and surround respectively the poles 19 and 21.

The device 11 is shown in the :form of a moving iron instrument having a movable part such as a rotatable armature 27. This armature may be constructed in any All.

suitable manner. Conveniently, the armature may be formed of a plurality of magnetic laminations 23 of soft iron or steel whch are fastened together in any sui-table manner. The armature may be mounted in the space between the poles 19 and 21 by a shaft 29 for rotation about the shaft axis relative to the poles. 'For this purpose, the shaft 29 may have secured thereto suitable bearing pivots 30 adapted to be mounted by suitable bearing screws (not shown).

The windings 23 and 25 are adapted to be connected to a circuit (not shown) for energization in accordance with an electrical quantity to be measured. The windings are so connected that they tend to establish magnetic fluxes which pass between the poles 19 and 211 in the same direction.

For depicting movement of the armature 27, a suitable indicating member, such as a pointer or pen, may be associated therewith. In the embodiment illustrated, a pen 31 is positioned for movement across the face of a suitable chart 32 to impose markings upon the chart. This chart may be constructed of any suitable material and is in the form of a circular disc mounted for rotation about its axis at a uniform rate by suitable means (not shown). The chart 32 may. be designed to rotate at any desired speed. -For example, the chart may rotate at the rate of one revolution per week and may be divided into Zones each representing one of the days of the week. Each of the zones may be divided further for indicating the hoursl of each of the days.

The pen 31 is provided with spaced pins 33 for pivotally engaging suitable spaced ears 34 carried yby a pen bracket 35. The pen bracket 3S may be supported in any suitable manner for rotation with the armature 27 about the axis of rotation of the armature 27. The pins 33 and ears 34 permit pivotal movement of the pen about an axis transverse to the axis of rotation of the armature.

In order to damp movements of the pen 31, a damping vane may be carried by the shaft 29 for rotation therewith. This damping vane may be formed of an electroconductive material, such as copper or aluminum. The vane 39 is conveniently secured to a hub 4t) carried by the shaft 29 for movement between the poles of a permanent magnet 41. As is understood in the art, movement of the vane 39 between the poles develops a force opposing such rotation which is dependent upon the rate of movement of the vane. The magnet 41 is conveniently mounted by a bracket 43 secured to the supporting plate 19 by screw and nut assemblies 44.

The pen 31 is biased by means of a spiral spring 45 toward one end of its path of movement. The spring 45 has its outer end secured to a stationary portion of the instrument and has its inner end secured to the movable pen assembly in any suitable manner.

In order to supply a suitable marking medium, such as ink, to the pen 31, a suitable ink container which conveniently may be in the form of a sealed compressible sack 47 is provided. The sack 47 may be formed of any suitable material, such as a plastic material, and is mounted by means described hereinafter. The sack 47 is located such that the ink level is slightly beneath the tip of the pen.

In order to feed ink from the sack 47 to the pen 31, there is provided a suitable length of flexible tubing 51 which extends between the sack 47 and the pen 31. In the past, it has been the practice to utilize tubing formed of a plastic material to feed ink from an ink container to a pen. Although plastic tubing possesses a number of desirable features, it also possesses certain inherent undesirable characteristics which adversely affect the operation of recording instruments. As an example, plastic tubing exhibits permeability to gases which may result in failure of the inking system due to the formation of air or gas bubbles in the tubing.

According to the present invention, the tubing 51 is and repetitions manner.

,suming operations.

e) formed of a suitable metallic material having dimensions which render the tubing flexible and which permit free and unimpeded ink ow through the tubing. The tubing 51 is preferably formed of a spring material. For example, the tubing 51 may be constructed of stainless steel or an alloy of beryllium and copper which are well known spring materials. Such materials are also impermeable to gases, exhibit negligible memory effects and possess negligible temperature coefficients. In the particular embodiment illustrated it is desirable that the tubing 51 have an inner diameter of approximately .G inch and an outer diameter of approximately .018 inch.

One end of the tubing 51 may project into additional tubing S2 which may be formed of a plastic material and which has an end into which projects an end of the sack tubing 52a. The other end of the tubing 5l may extend into plastic tubing 53 which is connected to an extension 54 o the pen 31. A portion of the tubing 51 intermediate the ends is curved substantially about the axis or rotation of the armature 27 as best shown in FIG. l.

The tubing 53 may be threaded through an opening provided at the free end of a rod 55 which is secured to the bracket 35. It is observed that the adjacent end 53a of the tubing 53 extends along a line which is common to the axis defined by the pins 33 to engage the extension 51talong such line. This arrangement minimizes the effect of the tubing upon the pressure exerted by the pen 31 upon the chart 32. Ink is supplied to the chart .32 by a combination of syphoning action and capillary attraction at the tip of the pen 31. For this purpose the pen tip is formed with a capillary bore.

When tubing of considerable length and flexibility, such as the tubing 51, is utilized to supply ink to the pen 31, it has been observed thatunless the tubing is suitably arranged, movements ofthe tubing in response to repeated movements of the pen will be inconsistent and nonrepetitious. It has further been noted that such movements of the tubing may produce undesirable movements of the pen and may also adversely aiiect calibration of the instrument.

In accordance with the present invention, the tubing 51 is in the form of a spring arranged such that movements of the tubing are consistent and repetitions in response to repeated movements of the pen whereby the elect of the tubing upon the pen may be substantially compensated in the calibration of the instrument. In the preferred embodiment of the invention illustrated, the tubing 51 is of helical formation to provide a spring construction. Other formations may also be employed such, for example, as a Zig-Zag formation. As illustrated in the drawings, one end of the tubing S1 is secured to the support plate 1t) by means of spaced ears S7 which clamp the end of the tubing 51. The other end of the tubing S1 is secured to the pen bracket 35 by means of a screw 59. The arrangement is such that the tubing 51 moves substantially in a plane which is transverse to the axis of rotation ot the armature 27. The spring construction of the present invention may be employed to advantage with tubing formed of materials other than metallic materials.

With this spring construction, movements of the tubing 51 caused by repeated movements of the pen 31 are observed to follow a predetermined course in a consistent This results in the application of a substantially constant torque by the tubing to the pen for a given energization of the measuring device. As a consequence movements of the tubing do not adversely aiiect the calibration of the instrument.

In order to initiate the iiow of ini'` from the sack 47 through the intermediate tubing to the pen 3l, it has previously been the practice to manually compress the sack to force ink therefrom into the tubing. This procedure involves a number of cumbersome and time con- For example, it has heretofore been necessary to manipulate certain portions of the recording instrument to expose the sack, remove the sack from its holder, compress the sack to force ink therefrom and finally return the sack to the holder.

In the present invention, means are provided for compressing the sack to initiate ink iiow Without disturbing the instrument mechanism and without handling of the sack. ri`he invention further provides improved mounting means to securely mount the sack in an operative position against accidental displacement. Preferably, the sack compressing means and the sack mounting means includes common parts.'

Referring now to FIGS. 3, 4 and 5, the combination sack compressing and mounting means is illustrated as including a pair of resilient members 61 and 63 which are each secured for deiiection towards and away from the other. The members 61 and 63 are formed of spring material, such as Phosphor bronze, and may be secured to the plate 1t).

As shown in FIG. 3, the member 61 is of substantially U-shaped configuration including a pair of spaced plate portions 65 and 67 connected by a base 69. The member 61 is mounted by means of a projection 71 of the plate portion 67 which passes under an extension 73k of the support plate iti, and also by a screw and nut assembly which engages a part of plate portion 67. The plate portion 65 of the member 6l. is arranged to c0- operate with a plate portion 77 of the member 63 to securely retain the sack 47 in an operative position. The plate portion 77 further serves to compress the sack as will presently appear.

The member 63 is of substantially L-shaped configuration as viewed in FIG. 3 including the plate portion 77 and a pair of transverse arms 79 and 31. The arm S1 may be secured to the support plate 10 by the assembly 75. As shown in FIG. 5, the plate portion 77 includes an extension 83 which engages a plunger 85 which is slidably'mounted in an opening of the support plate 10. In order to permit movement of the plate portion 77 towards and away from the plate portion 65, the base 69 of the member 61 is provided with a slot 37 `through which the extension 83 projects as shown in FIG. 5.

In FIG. 3, the sack 47 is illustrated in its normally retained operative position. As there` shown, the neck of the sack 47 is normally pinched between the ends of the plate portions 65 and 77 with the sack bottom engaging the base 69 of the member 61. As shown in FIG. 5 the sack-pinching portions of the portions 65 and 77 are clear of the tube 52a to avoid pinching of the tube 52a. In order to permit installation and removal of the sack from its retained position, the plate portion 65 may be deformed from its normal biased position to a position permitting insertion or withdrawal of the .sack through the space between the pinching ends of the plate portions 65 and 77.

In order to compress the sack 47 to initiate the How of ink, it is only necessary to displace the plunger 8S from the position shown inrFIG. 3 to the position illustrated in FIG. 4. This action causes movement of the plate portion77 from its non-compressing position of FIG. 3 to the compressing position shown in FIG. 4. It is noted that as the plate portion 77 moves towards its sack compressing position, the pinching end of the plate portion 77 is moved away from its sack-pinching position so as not to impede the flow of ink from the sack to the tubing. After the ink iiow is initiated in the abovedescribed manner, the plunger 85 may be released to return to its normal position shown in FIG. 3 under the bias exerted by the plate portion 77.

This application is a division of my copending application Serial No. 754,774, tiled August 13, 1958, for Electrical Measuring Instruments, now Patent blo-3,026,165.

Although the invention has been described with'reference to certain specific embodiments thereof, numerous modiications are possible, and it is desired to cover all modifications falling within the spirit and scope of the invention.

I claim as my invention:

l. A supporting apparatus for ink sacks or the like comprising, a substantiaily U-shaped member having a pair of outwardly extending arms connected at their bases by a base member, an elongated member, first means pivotally supporting one portion of said elongated member intermediate the free end portions of said arms and adjacent said free end portion of one of said arms, said elongated member extending between said arms toward said base member and having an end portion adjacent said base member, said elongated member being cooperable with said base member and a iirst of said arms to provide a pocket for supporting the ink sack, second means continually urging said elongated member about its said supporting means in a direction away from said tirst arm to maintain said pocket of predetermined size, third means urging said free end portion of said rst arm in a direction toward said one portion of said elongated member to provide a restricted opening for said pocket to prevent accidental movement of the ink sack outwardly of said pocket, said free end portion of said first arm being movable against the force exerted by said third means to permit the passage of the ink sack through said opening.

2. A supporting apparatus for ink sacks or the like comprising, a substantially U-shaped resilient member having a base member with outwardly extending spaced arms terminating in end portions, an L-shaped resilient member having a shorter leg and a longer leg, means securing the outward end portion of said shorter leg and said end portion of one of said arms to a supporting member with the junction of said legs located between said arms and adiacent said end portion of the other of said arms, said longer leg extending toward said base member and in non-parallel relation to said one arm to form with said base member and said one arm a substantially triangular pocket, said longer leg being movable toward said one arm to decrease the size of said pocket, said one arm being flexible away from said junction to permit insertion of an ink sack into said pocket.

3. A supporting apparatus for ink sacks or the like comprising, a substantially U-shaped resilient member having a base with outwardly extending arms terminating in end portions, said base having an aperture therethrough, a substantially L-shaped resilient member having a shorter leg and a longer leg, said shorter leg being located be tween and extending transversely of said arms adjacent said end portions, said longer leg extending between said arms and through said aperture, said longer leg and one of said arms and said base cooperating together to provide a pocket, said one arm being biased in a direction t move its said end portion toward said shorter leg to provide a restricted access to said pocket, said longer lcg being biased in a direction away from said one arm to maintain a normal size pocket, said aperture being elongated and permitting movement of said longer leg against its bias and toward a irst of said arms to reduce the size of said pocket, said end portion of said one arm being movable against its said bias to enlarge said restricted access to said pocket.

4. A holder of the character described, a substantially U-shaped resilient sheet material member having a base wall and rst and second side walls, said side walls extending outwardly from said base wall in spaced relation, said base wall having an aperture therethrough, a support, means securing said iirst side wall to said support, an l.shaped member having a first portion secured in iixed relation with an outward end portion of said first wall and extending outwardly of said iirst wall toward said second wall, said L-shaped member having a second portion extending between said side walls and through said aperture, said aperture being of a configuration to permit rocking movement of said second portion toward and away from said second wall, said L-shaped member Cil being formed so that said second portion is normally urged to rock said second portion away from said second wall to provide a space between said second wall and the portion oi said second portion immediately adjacent said base wall, said U-shaped member being formed so that an outward end portion of said second wall is normally urged toward said first portion to provide a restricted passageway therebetween by which access may be obtained to a pocket formed between said second wall and said second portion and said base wall, and operating means carried by said support and operatively engaging a part of said second portion which lies outside of said U-shaped member and movable to rock said second portion toward said second wall to decrease the size of said pocket.

5. A holder of the character described, a substantially Ushaped resilient sheet material member having a base wall and first and second side walls, said side walls extending outwardly from said base Wall in spaced relation, an L-shaped member having a first portion secured in tixed relation with a portion of said first wail spaced from said base wall and extending outwardly of said first wall toward said second wall, said L-shaped member having a second portion extending between said side walls and toward said base wall, said L-shaped member being formed so that said second portion is normally urged to rock said second portion away from said second wall, to

rovide a space between said second wall and the portion oi said second portion adjacent said base Wall, said U-shaped member being formed so that an outward end portion of said second wall is normally urged toward said first portion to provide a restricted passageway therebetween by which access may be obtained to a pocket formed between said second wall and said second portion and said base wall, and operating means operatively engaging a part of said second portion and movable to rock said second portion toward said second Wall to decrease the size of said pocket.

6. in combination, a sealed readily deformable ink sack. having an ink containing portion and an outlet passageway for flow of inl; outwardly of said sack, said sack being suiiiciently deformable to be deformed by atmospheric pressure as a consequence of the outward ilow oi inl; therefrom, a substantially U-shapcd resilient sheet material member having a base wall and iirst and second side walls, said side walls extending outwardly from said base wall in spaced relation, an Lshaped member having a first portieri secured in fixed relation with a portion ot said first wail spaced from said base wall and extending outwardly of said first wall toward said second wall, said L-shaped member having a second portion extending between said side walls and toward said base wall, said Lshaped member being formed so that said second portion is normally urged to rock said second portion away from said second wail, to provide a pocket between said second wall and the portion of said second portion adjacent said base wall, said pocket being of substantially the size of said ink containing portion of said sack, said U-shaped member being formed so that an outward end portion of said second wall is normally urged toward said first portion to provide a restricted passageway therebetween by which access may be obtained to a pocket formed between said second wall and said second portion and said base wall, said ink containing portion of said sack being in said pocket and said outlet passageway extending through said restricted passageway, a portion of said sack being iocated in said restricted passageway and clamped between said second wall and said irst portion, one of said members having an aperture therein through which said outlet passageway extends, and operating means operatively engaging a part of said second portion and movable to rock said second portion toward said second wail to decrease the size of said pocket.

7. in combination, a sealed deformable ink sack having an ink containing portion and an outlet passageway for flow of ink outwardly of said sack, a substantially U- shaped kresilient sheet material member having a base wall and first and second side walls, said side walls eX- tending outwardly from said base wall in spaced relation, an L-shaped member having a rst portion secured in fixed relation with a portion of said first Wall spaced from said base wall and extending outwardly of said irst wall toward said second wall, said L-shaped member having a second portion extending between said side walls and toward said base wall, said L-shaped member being formed so that said second portion is normally urged to rock said second portion away from said second wall, to provide a pocket between said second wall and the portion of said second portion adjacent said base wall,

' said pocket being of substantially the size of said ink containing portion of said sack, said U-shaped member being formed so that an outward end portion of said second wall is normally urged toward said first portion to provide a restricted passageway therebetween by which access may be obtained to a pocket formed between said second wall and said second portion and said base wall, said ink containing portion of said 'sack being in said pocket and said outlet passageway extending through said restricted passageway, a portion of said sack being located in said restricted passageway and clamped between said second wall and said first portion, and operating means operatively engaging a part of said second portion and movable to rock said second portion toward said second wall to decrease the size of said pocket.

References Cited in the file of this patent UNITED STATES PATENTS 1,507,464 Clegg Sept. 2, 1924 2,065,279 Kline Dec. 22, 1936 2,932,776 Massa Apr. l2, 1960 

1. A SUPPORTING APPARATUS FOR INK SACKS OR THE LIKE COMPRISING, A SUBSTANTIALLY U-SHAPED MEMBER HAVING A PAIR OF OUTWARDLY EXTENDING ARMS CONNECTED AT THEIR BASES BY A BASE MEMBER, AN ELONGATED MEMBER, FIRST MEANS PIVOTALLY SUPPORTING ONE PORTION OF SAID ELONGATED MEMBER INTERMEDIATE THE FREE END PORTIONS OF SAID ARMS AND ADJACENT SAID FREE END PORTION OF ONE OF SAID ARMS, SAID ELONGATED MEMBER EXTENDING BETWEEN SAID ARMS TOWARD SAID BASE MEMBER AND HAVING AN END PORTION ADJACENT SAID BASE MEMBER, SAID ELONGATED MEMBER BEING COOPERABLE WITH SAID BASE MEMBER AND A FIRST OF SAID ARMS TO PROVIDE A POCKET FOR SUPPORTING THE INK SACK, SECOND MEANS CONTINUALLY URGING SAID ELONGATED MEMBER ABOUT ITS SAID SUPPORTING MEANS IN A DIRECTION AWAY FROM SAID FIRST ARM TO MAINTAIN SAID POCKET OF PREDETERMINED SIZE, THIRD MEANS URGING SAID FREE END PORTION OF SAID FIRST ARM IN A DIRECTION TOWARD SAID ONE PORTION OF SAID ELONGATED MEMBER TO PROVIDE A RESTRICTED OPENING FOR SAID POCKET TO PREVENT ACCIDENTAL MOVEMENT OF THE INK SACK OUTWARDLY OF SAID POCKET, SAID FREE END PORTION OF SAID FIRST ARM BEING MOVABLE AGAINST THE FORCE EXERTED BY SAID THIRD MEANS TO PERMIT THE PASSAGE OF THE INK SACK THROUGH SAID OPENING. 